In ordinary straight turning, the cutting tool moves along a line parallel to the axis of the work, causing the finished job to be the same diameter throughout. However, when cutting a taper, the tool moves at an angle to the axis of the work,...Continue reading »
The principal function of waterstops is to prevent liquids (e.g. water), water-borne materials and solids to pass through concrete joints. In essence, it aims at providing watertightness to the drainage channel. Besides, waterstops in drainage channels or box culverts can also serve two other purposes:...Continue reading »
Epoxy grout consists of epoxy resin, epoxy hardener and sand/aggregates. In fact, there are various types of resin used in construction industry like epoxy, polyester, polyurethane etc. Though epoxy grout appears to imply the presence of cement material by its name, it does not contain...Continue reading »
In determining the external stability of retaining walls, failure modes like bearing failure, sliding and overturning are normally considered in design. In considering the criterion of sliding, the sliding resistance of retaining walls is derived from the base friction between the wall base and the...Continue reading »
If on-site slump test fails, should engineers allow the contractor to continue the concreting works?
This is a very classical question raised by many graduate engineers. In fact, there are two schools of thought regarding this issue. The first school of thought is rather straightforward: the contractor fails to comply with contractual requirements and therefore as per G. C. C....Continue reading »
In a typical expansion joint, it normally contains the following components: joint sealant, joint filler, dowel bar, PVC dowel sleeve, bond breaker tape and cradle bent. Joint sealant: it seals the joint width and prevents water and dirt from entering the joint and causing dowel...Continue reading »
What is the situation when an engineer will use jacking at one end only and from both ends in prestressing work?
During prestressing operation at one end, frictional losses will occur and the prestressing force decreases along the length of tendon until reaching the other end. These frictional losses include the friction induced due to a change of curvature of tendon duct and also the wobble...Continue reading »
Fiddle-Bow lathe was used mostly for small work, generally metal work, was called a “fiddle-bow lathe,” on account of the method of driving it. In this lathe, which is shown in the figure below. The same idea of propulsion is used, that of a cord...Continue reading »
It must be noted, however, that although skill can only be acquired by practice, by “making shavings” as the saying goes, it is futile practising unless the basic principles are being applied. The basic principles are comprised of four main elements: The choice of the...Continue reading »
In the case of woodturning there is a bit more to it than motor skills because, with the right attitude of mind, it is within the power of the individual to alter the shape of the learning curve. The key to skill is attitude. What...Continue reading »